The present invention relates to a coffee machine.
More particularly, the invention relates to an espresso coffee machine.
Traditional espresso coffee machines, of the Italian type used in bars, restaurants and coffee shops, are constructed to brew coffee by passing hot water through a quantity of ground coffee which is placed into a filter inside a receptacle.
Removal of the receptacle, used coffee and filter, and reinstallation of the receptacle with new supplies, is not difficult but does require the services of an operator who must be paying attention to this work. In restaurants and similar establishments these operators are, however, often distracted by other demands which are made on them. This having been recognized, prefabricated pods of coffee have been developed which require no filter, no pouring, and no measuring, but are simply slipped into a chamber provided for them in the coffee machine. Unfortunately these pods, each of which equals one brewing measure and is formed by compressing ground coffee between two layers of water-permeable filter paper, cannot be used in the conventional coffee machines. The pods do not fit the receptacles of those machines and are only suitable for use in an extraction chamber of the type disclosed in U.S. Pat. No. 4,254,694. Nevertheless, in view of their advantages it would evidently be also desirable to be able to use such pods in conventional machines.